[Username1]

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Hi - The lines on the screen line up perfectly to point to a horizontal drive pulse, or
possibly a harmonic, or ringing etc. I don't think it's injected anywhere, but it may
be on the power supply lines, any of them. Do you have a scope? You may need
one to find this. I would look at each of the voltage sources for this 1/15734
or multiple showing up on voltage source lines. All these sources are also
providing bias for the picture tube, & it's drivers, so if it's in the power
supply, you can bet it's in the tube when no picture is present to begin
with, and it's still there with picture information. So set your scope
to capture several H pulses possible set sync to the H pulse,
and look for itsy bitsy H frequency ripple in the power supply.

You see your power supply has lots of choke's in it along with
caps to filter out flyback noise at each source point.

I doubt this came from the factory like that, the Japanese
are very meticulous about how their stuff operates....

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